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Nonabelian localization in equivariant K-theory and Riemann-Roch for quotients

Dan Edidin·William Graham
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Abstract

We prove a localization formula in equivariant algebraic $K$-theory for an arbitrary complex algebraic group acting with finite stabilizer on a smooth algebraic space. This extends to non-diagonalizable groups the localization formulas H.A. Nielsen in equivariant $K$-theory of vector bundles and R.W. Thomason for higher $K$-theory of equivariant coherent sheaves. As an application we give a Riemann-Roch formula for quotients of smooth algebraic spaces by proper group actions. This formula extends previous work of B. Toen for stacks with quasi-projective moduli spaces and the authors for quotients by diagonalizable groups.

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Dan Edidin, William Graham. 2005-07-13. Nonabelian localization in equivariant K-theory and Riemann-Roch for quotients. https://arxiv.org/abs/math/0411213

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